From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>,
        Justin Pryzby <pryzby@telsasoft.com>,
        Dilip Kumar <dilipbalaut@gmail.com>
Subject: Re: longfin and tamandua aren't too happy but I'm not sure why
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Comments: In-reply-to Robert Haas <robertmhaas@gmail.com>
	message dated "Tue, 27 Sep 2022 17:21:54 -0400"
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Date: Tue, 27 Sep 2022 17:50:07 -0400
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Robert Haas <robertmhaas@gmail.com> writes:
> On Tue, Sep 27, 2022 at 4:50 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> There is a second problem that I am going to hold your feet to the
>> fire about:
>> (lldb) p sizeof(SharedInvalidationMessage)
>> (unsigned long) $1 = 24

> Also, I don't really know what problem you think it's going to cause
> if that structure gets bigger. If we increased the size from 16 bytes
> even all the way to 32 or 64 bytes, what negative impact do you think
> that would have?

Maybe it wouldn't have any great impact.  I don't know, but I don't
think it's incumbent on me to measure that.  You or the patch author
should have had a handle on that question *before* committing.

			regards, tom lane